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AbstractClimate change and deoxygenation are affecting fish stocks on a global scale, but disentangling the impacts of these stressors from the effects of overfishing is a challenge. This study was conducted to distinguish between climate change and mismanagement as possible causes for the drastic decline in spawning stock size and reproductive success in cod (Gadus morhua) and herring (Clupea harengus) in the Western Baltic Sea, when compared with the good or satisfactory status and reproductive success of the other commercial species in the area. Available data on water temperature, wind speed, and plankton bloom during the spawning season did not reveal conclusive correlations between years with good and bad reproductive success of cod or herring. Notably, the other commercial species in the area have very similar life history traits suggesting similar resilience against stress caused by climate change or fishing. The study concludes that severe, sustained overfishing plus inappropriate size selectivity of the main fishing gears have caused the decline in spawning stock biomass of cod and herring to levels that are known to have a high probability of impaired reproductive success. It is pointed out that allowed catches were regulated by management and adhered to by the fishers, meaning that unregulated fishing did not occur. Thus, mismanagement (quotas that were too high and gears that selected too small sizes) and not climate change appears to be the primary cause of the bad status of cod and herring in the Western Baltic Sea.

AbstractClimate change and deoxygenation are affecting fish stocks on a global scale, but disentangling the impacts of these stressors from the effects of overfishing is a challenge. This study was conducted to distinguish between climate change and mismanagement as possible causes for the drastic decline in spawning stock size and reproductive success in cod (Gadus morhua) and herring (Clupea harengus) in the Western Baltic Sea, when compared with the good or satisfactory status and reproductive success of the other commercial species in the area. Available data on water temperature, wind speed, and plankton bloom during the spawning season did not reveal conclusive correlations between years with good and bad reproductive success of cod or herring. Notably, the other commercial species in the area have very similar life history traits suggesting similar resilience against stress caused by climate change or fishing. The study concludes that severe, sustained overfishing plus inappropriate size selectivity of the main fishing gears have caused the decline in spawning stock biomass of cod and herring to levels that are known to have a high probability of impaired reproductive success. It is pointed out that allowed catches were regulated by management and adhered to by the fishers, meaning that unregulated fishing did not occur. Thus, mismanagement (quotas that were too high and gears that selected too small sizes) and not climate change appears to be the primary cause of the bad status of cod and herring in the Western Baltic Sea.

Since the Paris Agreement adopted in 2015, global societies are increasingly aware of the needs to limit global warming to 1.5 C and reach global carbon neutrality by 2050. However, current commitments of global societies are not sufficient, party owing to the lack of cost-effective decarbonization measures. The SolarEV City concept is proposed for cost-effective urban decarbonization combining rooftop PV with EV through bi-directional charging in a city scale. In this study, we conducted techno-economic analyses to test the concept in Paris and Ile-de-France. PV+EV systems are found to add value to rooftop PV systems raising selfconsumption and self-sufficiency, when the roof coverage by PV is reached to 50-60% for Paris and 20-30% for Ile-de-France, allowing to bypass expensive stand-alone battery storage. The system allows CO2 emissions reduction through accelerated development of EV.

Since the Paris Agreement adopted in 2015, global societies are increasingly aware of the needs to limit global warming to 1.5 C and reach global carbon neutrality by 2050. However, current commitments of global societies are not sufficient, party owing to the lack of cost-effective decarbonization measures. The SolarEV City concept is proposed for cost-effective urban decarbonization combining rooftop PV with EV through bi-directional charging in a city scale. In this study, we conducted techno-economic analyses to test the concept in Paris and Ile-de-France. PV+EV systems are found to add value to rooftop PV systems raising selfconsumption and self-sufficiency, when the roof coverage by PV is reached to 50-60% for Paris and 20-30% for Ile-de-France, allowing to bypass expensive stand-alone battery storage. The system allows CO2 emissions reduction through accelerated development of EV.

High-flow tidal stream environments, targeted for tidal turbine installations, exhibit turbulent features, at fine spatio-temporal scales (metres and seconds), created by site-specific topography and bathymetry. Bed-derived turbulent features (kolk-boils) are thought to have detrimental effects on tidal turbines. Characterisation of kolk-boils is therefore essential to inform turbine reliability, control, and maintenance strategies. It will also improve the understanding of potential ecological interactions with turbines, as marine animals use these sites for foraging. Unmanned aerial vehicle (UAV), or drone, imagery offers a novel approach to take precise measurements of kolk-boil characteristics (distribution, presence, and area) at the surface. This study carried out sixty-three UAV surveys within the Inner Sound of the Pentland Firth, Scotland, UK, over four-day periods in 2016 and 2018. Kolk-boil characteristics were examined against relevant environmental covariates to investigate potential drivers of presence and area. The results show that distribution at the surface could be predicted based on tidal phase, with current velocity significantly influencing presence above 3.0 m/s. The technique can be used to inform turbine development, micro-siting and provide better understanding of environmental implications of turbine operation. Finally, it highlights the suitability of UAVs for capturing rapid fine-scale hydrodynamic data in the absence of in situ measurements.

High-flow tidal stream environments, targeted for tidal turbine installations, exhibit turbulent features, at fine spatio-temporal scales (metres and seconds), created by site-specific topography and bathymetry. Bed-derived turbulent features (kolk-boils) are thought to have detrimental effects on tidal turbines. Characterisation of kolk-boils is therefore essential to inform turbine reliability, control, and maintenance strategies. It will also improve the understanding of potential ecological interactions with turbines, as marine animals use these sites for foraging. Unmanned aerial vehicle (UAV), or drone, imagery offers a novel approach to take precise measurements of kolk-boil characteristics (distribution, presence, and area) at the surface. This study carried out sixty-three UAV surveys within the Inner Sound of the Pentland Firth, Scotland, UK, over four-day periods in 2016 and 2018. Kolk-boil characteristics were examined against relevant environmental covariates to investigate potential drivers of presence and area. The results show that distribution at the surface could be predicted based on tidal phase, with current velocity significantly influencing presence above 3.0 m/s. The technique can be used to inform turbine development, micro-siting and provide better understanding of environmental implications of turbine operation. Finally, it highlights the suitability of UAVs for capturing rapid fine-scale hydrodynamic data in the absence of in situ measurements.

Vehicles are burning fuels inefficiently. Nowadays, there is a strong correlation between CO2 emission and climate change. The article estimates a theoretical environmental impact of biofuel mixtures on the transport sector. A high ratio of road transportation in CO2 emission caused by humanity made necessary to research the estimation of the environmental impact of biofuel mixtures. We have to clarify the emission of the transport sector in order to get information about the role of the impact that is a further step to a sustainable society. Sustainable development is a kind of development where the pace of technical development, the satiation of increasing supply and the raw materials and resources of the Earth are poised so that the rate of living and the opportunities of the future generations should not decline. One of the major goals of transport policy of the European Union is sustainable mobility. For this reason, transportation systems must be developed and standardized and the effectiveness of transportation service must be increased while environmental pollution must be decreased or prevented. There is a justifiable demand put forward by the society to moderate the environmental impacts caused by road transportation. This article deals with modelling the environmental impact of ethanol‐gasoline mixtures and diesel oil‐ethanol‐biodiesel mixtures.